This invention relates to climbing equipment, specifically to the retrieval of such equipment.
In mountain or rock climbing, safety is of prime importance. A climber prevents injury to him or herself by relying on a safety rope to prevent falling potentially fatal distances. A typical climbing rope is usually composed of nylon or other man made compounds, 50 to 60 meters long and 9 to 12 mm in diameter. The climbing rope is carefully placed on the ground and one end is passed through a mechanical device known as a belay tool. This device is then attached to the safety harness of the member of the climbing team designated the belayer. The climbing rope is fed out of the belay tool and tied to the harness of the other member of the climbing team, the climber.
The belayer loosely holds the climbing rope approximately 30-cm from the point at which it enters the belay tool. By changing the angle the rope enters the belay tool, the belayer adjusts the amount of friction on the rope. If the belayer holds it parallel to the rope that leaves the tool and is attached to the climber, the friction is very low. Conversely, if the rope is held at a 90-degree angle to the tool, the friction is sufficiently high to keep the rope from passing through the tool. This action is used to allow the rope to either follow the climber as he or she ascends, or to stop the rope from passing through the tool if the climber falls, thus preventing the climber from falling excessive distances.
For safety, after ascending 2 to 3 meters above the ground, the climber must attach the climbing rope to an anchor location on the rock face. In so-called sport climbing, this location is the first of many permanent, man made anchors bolted to the rock face. In so called traditional or mountain climbing, these man made locations are not available and the climber searches out a place in the rock face for a temporary anchor point. The temporary anchor point is made using one of the mechanical contrivances carried on the climbers' safety harness. They include various shaped cams, nuts, steel shafts and formed metal objects. The type of device used to manufacture the anchor point depends on the rock composition and its natural surface. As an example, the climber may decide to place a spring-loaded cam into a crack in the rock face. The temporary anchor point manufactured in this way is intended to have the same strength and stability as a man made anchor point.
Both the permanent anchors bolted to the rock face and temporary anchor locations made by the climber using a mechanical device have a hole or ring manufactured into them to allow a piece of climbing equipment, called a draw, to be attached.
A draw is assembled with a sling and two carabiners. A sling is a band of heavy nylon webbing, usually 10 mm to 45 mm in width and 20 cm to 2.4 m in length. The ends of the webbing are sewn together to form a continuous loop. A carabiners is a mechanical device, usually D shaped, with a spring-loaded gate on the straight side that automatically shuts when tension on the gates return spring is released. Two carabiners are clipped onto a sling and the assembly is then known as a draw.
As explained above, the climber attaches one of the carabiners on the draw into the permanent man made or temporary anchor. He or she then opens the gate on the second carabiner, inserts the climbing rope and allows the gate to close.
At any time after the first draw is in place, the belayer can prevent the climber from impacting the ground should he or she fall from the rock face. If the climber falls, the belayer quickly pulls the rope to a 90-degree angle from the face of the belay tool. This action stops the rope from passing through the tool. The climber falls until the rope is pulled taut from his or her safety harness, through the draw and down to the belayer. The climbers' weight on the rope is offset by the belayers' weight on the rope and the climbers' fall is arrested. The climber regains his or her position on the rock face and the climb is continued.
The climber ascends until all but last few meters of the safety rope has passed through the belayer's belay tool. The climber then finds a stable position on a ledge, crack or outcropping and attaches a belay tool to his or her harness. After untying the safety rope from his or her harness and passing the rope through the belay tool, the climber becomes the belayer. The original belayer then takes their end of the rope out of their belay tool and ties it to their safety harness. In this manner the original climber now becomes the belayer and the original belayer becomes the climber. As the climber ascends the rock face, he or she retrieves the draws and any mechanical devices that were used to manufacture temporary anchor points. As the climber ascends, the belayer continuously pulls the in safety rope until the climber reaches the position of the belayer. If the climber should fall off the rock face, the action of the belayer, even though they are now positioned above the climber, is the same. The belayer quickly pulls the rope to a 90-degree angle from the face of the belay tool and the climbers fall is arrested.
After the climber reaches the position of the belayer, the draws and mechanical devices are attached to the safety harness of the person making the next vertical ascent and the climb continues. This process continues until the summit is reached or the party can no longer ascend because the requirements of the climb exceed the capabilities of the climbing team. In either situation, the team must then return to the ground.
Returning to the ground is usually accomplished by rappelling. To rappel, one of the climbers attaches a sling directly to the last anchor point reached. If this point is a man-made anchor, the sling is passed through the hole manufactured in the anchor. This is the same hole into which a carabiner on a draw was placed during the climb. A natural rappel point is usually a tree, a crack in the rock face or a large rock outcropping. If a tree is used, the sling is passed around the base. If a crack is used, a small rock, called a chockstone, is jammed into the crack and the sling is passed around the chockstone. If a large rock outcropping is used, a long sling is passed around the outcropping. In all the situations described above, equal amounts of the sling are then positioned on each side of the rappel point.
The climbing rope is then passed through the two open loops of the sling that were formed when the sling was passed through or around the rappel point. The climbing rope is pulled through the two loops in the sling until the entire rope is hanging down below the climbers in two equal lengths. Both lengths of the rope are passed through the first climbers' belay tool and the climber then rappels the length of the ropes. The second member of the team follows the first in this manner. To retrieve the rope, one climber pulls on one of the lengths hanging down from the sling, until the rope falls free from the sling and lands at the climbers' feet. A new rappel point is then prepared as described previously and the team rappels down to the next level. This procedure is repeated until the climbing team reaches the ground.
Because the climbing rope is pulled through and subsequently free of the sling, the sling must usually be abandoned. During a high and difficult climb, up to a dozen slings must be left behind. This is not only costly and unsightly, but also environmentally undesirable.